Re: e1000 full-duplex TCP performance well below wire speed

From: David Miller
Date: Wed Jan 30 2008 - 08:53:37 EST


From: Bruce Allen <ballen@xxxxxxxxxxxxxxxxxxxx>
Date: Wed, 30 Jan 2008 03:51:51 -0600 (CST)

[ netdev@xxxxxxxxxxxxxxx added to CC: list, that is where
kernel networking issues are discussed. ]

> (The performance of a full duplex stream should be close to 1Gb/s in
> both directions.)

This is not a reasonable expectation.

ACKs take up space on the link in the opposite direction of the
transfer.

So the link usage in the opposite direction of the transfer is
very far from zero.
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